Photographic plate element and process of preparing same



J. HERBERT Jan. 1, 1935.

PHOTOGRAPHIC PLATE ELEMENT AND PROCESS OF PREPARING SAME Filed Nov. 27,1951 I Jacob If Irv/verifier.

'5 applicationgi Patented Jan. 1, 1935 '7 T mit M This application; 1 isa a.1-refi1ing1;of,z1milraoliginal application Ser. No. 1411,130,.afiledziDecember 2, 1929,: but withira more complete f'disclosure;zan'd is therefore-inpart a continuation-zofsaidoriginal;

I This inventionzrelates to producing permanent ink 'delineations anidesignsizon: glass; for ;ex-,

ample, in connection with the art' of photography,

and is more particularly .concerned withithe proc-j ess or' methodJofrapplying;to;aetranslucent plate element, lines of markings thatvisually delineate thev photographic field in terms of linear units ofmeasurement, .and alsomis 1 concerned with the resultant product ortranslucent: plate element; .In photography for commercial andindustrial use including engraving, .jarchitectural photog-.

raphy, etc., a. high. degree of I exactness :of size and placement ofthe object onthepphotograph are essential to producesuccessfulsresultsu. .Only approximatelyand only roughly :has; this"been effected in'the past,iand*.usually by-the .use of 'a hand rule inconjunction with. a focusing surface,

as,: for example, the. usual v ground glass. :"such 7 procedure notonly-lacks in accuracy butarequires much time and the results arenotipermanentm 1,; I In architectural photography; both of interiors and"exteriors; .not only Imust a camer'aibe ;;'set

up 1 with accuracy I (this is: frequently. difiicult; because of .thelack of guiding lines) but the viewer object to be photographedmustybeplaced for correct'lines or soecalled perfect: perspectiveordrawing lines. 'I'hi'sistrue also in photographe ing objects such asfurniture forqillustration andadvertising. In photographing for engraveing work, extreme-.exactitude :of scale and place-a mentli's"imperative. 1 I I An important object of the present invention is toprovide a focusing surface sealed in subdivisions preferably in thevertical and horizontal, and in'terms'of linear measurement, withoutimpairing the clarity of focusing vision, whereby the focusing of theobject onthe focusing sur --v face to secure accurate sizing'andplacement on the photographic surface may beeffected visually withreferenceto a focusingsurface delineating known linear values-andinterrelation. p The invention therefore relates both to the methodwhereby the marking or delineation is effected and also to the resultingarticle or' product.

Referring to the drawing wherein isrepresented a single embodiment onlyof the product re-,

sulting from my process- Fig. 1 15a perspective view of view camera andof the so-called ground glass S' SEATEN V H ,esseas f anomesirsre F QF5r feelea ere I Ha e Newtom lvil asisi t te 112?! the back of a e aisme.

holder'yvitha ground glasstreatedm accordance with my invention;

Fig. 2 is a plan view of vrs d sealepfa small po tion oi es d'e estolone surface of which the delineationsormark-t ne r ave. b en pplied.

:R f rr ns only to the sin e efi d ien i 9 V the; inventionhere;illustrated, the back 011 the, bellows; portion 0f a; view camerais indicated, at. 1., This may ;be of any usual construction; ep e ed'as'rhav n f ur d ,t. & t ;v sprin s 2, 2 wh ch r c ive he, nsfiwun nvthrame.. rd r: fo -the .f ro d lass? S parts may be of anysuitableconstruction and need not be further described exceptingtojstate that, i cco nc wi t e'usual, r. ree v t e:

m o e heraceupon w i ex s 1 1-159. 5

beme is. i se t qbetwe ntheba 1am, the,

c of the cam a; w e pon thekfilme fetheri ree iyi u ce i m rte nan th sings;- tie e$ the 1de to position-i lhe soi alled if e nd; la s? on yeui len rans u ent plat el m nt/ 1s. re ented; n Figs! 1 2, fend 3 a 15.111 themur e vo m exp ria me ta i a I ve. ewerte n d ha h di ery e qu l se et ati e eryen w l n t, r i-i ce ve heli ee s ideli ie n hma nere t,20. v :frame 4 which is drawn as gusualaway from ,the, L;

any

to re them, e man nt and r h sma nl u t ther e th t s lehi ord x1a,sr9und cla e ell d ewe end-is heref re-e u v th ck HESS rrrevfatashe, ee' tienn-t t e s r ace of a the glass of the demarcations crimes nbcause the. application of heavy pressure tp ei t t h t sarea- S ehnve'na I breaks the glass. I have found that in order to make thedelineations'or markings permanent,

they must'be applied-under heavy pressure. If

heavy pressure he resortedto, as, for'example,

one thousand pounds more or less,- such pressure wouldbreak,substantially invariably, the usual ,ground glass made by a rollingprocess.-

Accordingly, I employ plate glass indicated at, 5,

and the surface thereof may be ground in the usual manner. Sucha glasswill sustain the heavy pressure which I find it highly desirable toemploy in applying the delineations or markings to the surface thereofand in such a way as actually to embed those markings into the, surfaceof the glass.

The markingsmay, of course, be widely varied within the scope of myinvention, but inthedis- 55 closed embodiment of the invention I haverepresented vertical lines 6 and horizontal lines 7 tum visuallysubdivided by a series, of finer and a more closely but. uniformlyspaced-vertical "and horizontal lines 9, 10, spaced for example, one

quarter of an inch apart and sub-dividing the square 8 into smallsquares ll having hounding sides one quarter of an in ch long. 'I 'hemain division lines 6, '7 which bound the larger squares are preferablyslightly, heavier than vthemore closely spaced linesy9, l0, soas, toenable the eye quickly to estimate the area 'coveredby a group ofsquares 8 within which an object to ice-photo.- graphed appears on thesurface of the ground plate glass and enables me camera to be" focusedto bring an object within a "desired delineated areafo'n the groundplate glass.

The said vertically and horizontally delineated lines5 6, 9, lQ- enablethe camera to be set up andfocused as tobrin g the 'lines'of the objectto bephotographed, as in architectural or dis-' play photography, intocorrect and proper 'rel ation to the vertical andthe horizontal "ontheground glass, and therefore on the photographic surface of the plateor'film. In photographing for engraving work, the relatively finesub-divisions-11 of the-squars-B enable the object to be focused on theground plate glass to the exact dimensionand placement required by thephoto'- graphic reproduction. v a v k In'applying the markings to theground plate glass I employ'a waterproof applying such ink to thefunderor 'coeacting surface of the platen of the-' p ress. The ground plateglass?) is laid in the press so that theface'of the platen"- havingthesaid lines of waterproof 'inkth'ereon may be brought intoieontactwith-the said plate glass 5. I preferably employ very-great Pli ssure,"as, for example, one thousand pounds to the platen and the resul-tisvthat the waterproof ink becomes actually embedded in the structure ofthe-glasses indicated in'Fig. '3; ;In said Fig.-'3, I have exaggeratedat 12 thenOririal ground glass suriacle oi the plate glass, and at 13have indicated oneof thewaterproof'ink lines. When the waterproof ink isapplied the} manner described, it 'is permanently retained "by thesurface of the'glass,'thereby providing a plate glass the markings ofwhich will notbecome'obscured or impaired 'in any way. a

Having thus described one embodiment of my invention and the best modeknown to me for practising the method of the invention, I desire it tobe understood that although specific terms are employed, they are usedin a generic and descriptive sense and not for purposes of limitation,the scope of the invention being set forth in the following claims.

1. That rocesam ground lass and like translucent plate elements forcameras consisting of providing a ground plate glass and applying linesor other marks thereto under such -heavy pressureas to impress saidlines permanently into "all surface irregularities of the strucitur'e'ofthe-said glass and to insure a direct and fintimatebonglof said linesand the glass throughout the entire extent of the lines, therebypermanently delineating visually the glass in the desired pattern.

2; ."I'haa process oi marking ground glass and like translucent plateelements consisting of pro.- viding a ground vplate glass and applyingwater-.- proof ink lines. or-other marks thereto under such heavypressure as to impress said lines per-w man'ently into all surfaceirregularities ofthe structure of the said glass and to insure adirectand intimate bond of said lines. and the glass throughout the entireextentroftheglines, thereby permanently delineating visually the :glassin the desired pattern; a

3. As anew article of manufacture, atransr: lucent glass .iplateelement, said article comprising. a sheet of greund plate glasshavinglines or other marks of waterproof ink so impressed upon the :glass thatall surface irregularities of the structure ofthe glass along the zoneof said line are filldby theink, the ink having direct and intimatelybonded relation iwith the glass structure throughout the entire, extent'JOf the. lines, said lines thereby providing permanent delineationlofthe glass in the desiredpattern and form.

"4. "As a new article ofmanufacture, a. focusing plate forma camera,consisting of ,a sheet of ground plate glass having'aiocusingfield'deline: ated thereonpand having visually" indicated areal unitsand subunits within said field, said'field and its units and'suhunitsformed=by waterproof ink lines impressed upon'saidplate glass,in the ade-i sired iarra'ngenient and configuration, and in whichthe'ink has penetrated and occupies an underlying=gsuifaceirregularities, of the glass thereby formingadirectuninterruptediand substantially permanentrbond with the glassstnuce ture throughout the entire-extent vof the lines.

' J AGOB, HERBERT.

